sepharose and Stomach-Neoplasms

Procedure of endoscopic submucosal dissection (ESD) has been introduced widely for treatment of early gastric cancers. For such specimens, accurate pathological diagnosis, especially concerning depth of the invasion and exposure to margins, is essential to decide on the necessity of additional treatment. Therefore, easy and reliable tissue-processing method for multiple cut specimens is needed. The authors report here a new double embedding technique for specimens of ESD.. Formalin-fixed whole specimen was superficially wrapped by agarose (the first embedding), and the tissue-agarose block was cut at 2-3 mm intervals. Each cut specimen was laid down with 90° rotation. This procedure permitted 'on edge' embedding of thin tissues in paraffin (the second embedding) and subsequent preparation of perpendicular section to the tissue surface. The authors compared the handleability and stainability among several media including various types of agar, agarose and gelatin for first embedding. A survey by questionnaire was carried out on handleability and/or impression on various tissue-processing steps from pathology technicians.. Among the media examined, agarose showed the best solubility in water and the best transparency on several representative stainings. According to the survey, pathology technicians seemed to feel that the present method was better than the usual tissue processing method, especially in shortened time consumption and accuracy of alignment of multiple tissues for ESD specimens.. The present new double embedding technique using agarose provides not only an easy and reliable embedding procedure for technicians but also accurate and exact diagnosis for pathologists.

Topics: Agar; Dissection; Formaldehyde; Gastroscopy; Gelatin; Humans; Paraffin Embedding; Sepharose; Staining and Labeling; Stomach Neoplasms; Tissue Embedding

Porphyrans, the sulfated polysaccharides, are the main components of Porphyra. The potential apoptotic activities of porphyran were evaluated using AGS human gastric cancer cells. Porphyran did not affect the growth of normal cells, but did induce cancer cell death in a dose-dependent manner. The addition of 0.1% porphyran also reduced DNA synthesis after 24 h of exposure, suggesting that porphyran inhibits cancer cell growth by both decreasing cell proliferation and inducing apoptosis. AGS cells treated with porphyran displayed a marked increase in poly(ADP-ribose) polymerase (PARP) cleavage, as well as caspase-3 activation. The ability of porphyran to promote apoptosis may contribute to its usefulness as an agent capable of significantly inhibiting cell growth in AGS human gastric cancer cells. Insulin-like growth factor-I receptor (IGF-IR) phosphorylation was decreased in porphyran-treated AGS cells compared to control cells, which correlated with Akt activation. Thus, porphyran appears to negatively regulate IGF-IR phosphorylation by causing a decrease in the expression levels in AGS gastric cancer cells, and then inducing caspase-3 activation.

Topics: Apoptosis; Caspase 3; Caspases; Cell Line, Tumor; Cell Proliferation; DNA Replication; Enzyme Activation; Humans; Phosphorylation; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-akt; Receptor, IGF Type 1; Sepharose; Signal Transduction; Stomach Neoplasms

Glycosaminoglycans (GAGs) in proteoglycan (PG) forms or as free GAGs are implicated in the growth and progression of malignant tumors. These macromolecules were investigated in human gastric carcinoma (HGC) and compared with those in human normal gastric mucosa (HNG). We report that HGC contained about 2-fold increased amounts of GAGs in comparison to HNG. Specifically, HGC showed 3- and 2.5-fold net increase in chondroitin sulphate (CS) and hyaluronan (HA) contents, respectively. Dermatan sulphate (DS) was slightly increased, but the amount of heparan sulphate (HS) was decreased. Of particular, interest were the quite different sulphation profiles of CS and DS chains in HGC in which, non-sulphated and 6-sulphated disaccharide units were increased 10 and 4 times, respectively, in comparison to HNG. On PG level, three different populations were identified in both HNG and HGC, being HSPGs, versican (CS/DS chains) and decorin (CS/DS chains). In HGC, the amounts of versican and decorin were significantly increased about 3- and 8-fold, respectively. These PGs were also characterized by marked decrease in hydrodynamic size and GAG content per PG molecule. Analysis of Delta-disaccharide of versican and decorin from HGC showed an increase of 6-sulphated Delta-disaccharides (Delta di-6S) and non-sulphated Delta-disaccharides (Delta di-0S) with a parallel decrease of 4-sulphated Delta-disaccharides (Delta di-4S) as compared to HNG, which closely correlated with the increase of CS content. In addition, the accumulation of core proteins of versican and decorin in HGC was also associated with many post-translational modifications, referring to the number, size, degree and patterns of sulphation and epimerization of CS/DS chains. Studies on the modified metabolism of PGs/GAGs are under progress and will help in deeper understanding of the environment in which tumor cells proliferate and invade.

Topics: Adenocarcinoma; Cell Division; Chondroitin Sulfate Proteoglycans; Decorin; Extracellular Matrix Proteins; Female; Gastric Mucosa; Glycosaminoglycans; Humans; Lectins, C-Type; Male; Middle Aged; Proteoglycans; Sepharose; Stomach Neoplasms; Subcellular Fractions; Versicans

A soft agarose clonogenic assay is presented which has been optimized for the growth of human gastrointestinal adenocarcinomas. Samples from 15 gastric and colonic solid tumors and from 2 noncancerous stomachs (control cultures) were disaggregated by treatment with collagenase at 37 degrees overnight. Colonies appeared 10 to 15 days after plating, with a cloning efficiency between 0 and 0.82%, which was markedly improved by a fibroblastic feeder layer. The results suggest a correlation between cloning efficiency and the degree of differentiation of the initial tumor. Histochemistry, electron microscopy, and a carcinoembryonic antigen immunofluorescence assay showed that the colonies consisted of cells with the same characteristics as those of the original tumor.. This colony formation assay appears to be potentially useful for assessing the stem cell pool of gastrointestinal tumors. It will be valuable for studying their response to chemotherapeutic agents in vitro. This clonogenic assay may also permit the establishment of cancer cell lines.

Topics: Adenocarcinoma; Carcinoembryonic Antigen; Cell Differentiation; Cell Division; Cell Line; Cells, Cultured; Colonic Neoplasms; Colony-Forming Units Assay; Gastrointestinal Neoplasms; Humans; Sepharose; Stomach Neoplasms

Leukocyte migration tests under agarose (Clausen technique) were performed in 28 patients tentatively diagnosed as having any malignancy with the use of a 3 M KCl-extract panel prepared from bronchogenic, gastric, colonic, renal, and mammary carcinoma, corresponding normal tissues, carcinoembryonic antigen (CEA), and human encephalitogenic protein (HEP). 17 out of 22 proven carcinoma patients showed sensitization by reaction with optimal concentrated KCl-extract of cancer from the same organ type as their own tumor. In some cases positive reactions could be observed also with normal tissue antigen (NTA) of tumor organ type (7/22) or with an additional carcinoma extract of organ type differing from patients own primary tumor (8/22). Gastrointestinal carcinomas, especially, showed sensitization to CEA (7/12) contrary to nongastrointestinal carcinomas (1/10). With HEP no positive reactivity could be found (0/10). With the use of tumor antigen panel (5 antigens) only few positive reactions (MI less than 0.80 or greater than 1.20) could be observed in 6 patients with nonmalignant diseases (1/30 tests) and 8 healthy blood donors (1/40 tests). A widespread individual screening program using tissue antigens for patients suspected of malignancies could give a pattern of reactivities and improve the recognition of cell-mediated sensitization against tumor tissues.

Topics: Aged; Antigens, Neoplasm; Breast Neoplasms; Carcinoembryonic Antigen; Cell Migration Inhibition; Colonic Neoplasms; Epitopes; Female; Humans; Immunity, Cellular; Kidney Neoplasms; Leukocytes; Lung Neoplasms; Male; Middle Aged; Myelin Basic Protein; Neoplasms; Sepharose; Stomach Neoplasms